While touring Italy years ago I was shocked that the men & women share the same restrooms. These were located at the highway rest stops. I was totally uncomfortable when a woman sat in the next stall and took a dump. And then there was always a woman by the sinks to hand out paper towels with the expectation of getting a tip. My tip was....get the hell out of my way. LOL!!!!!!
Answer on As a straight person, if public restrooms allowed both sexes access would you have sex there in a stall?
No, public bathrooms are gross.